<?php
header('Content-type:text/html; Charset=utf-8');
$appid = 'xxxxx'; //https://open.alipay.com 账户中心->密钥管理->开放平台密钥，填写添加了电脑网站支付的应用的APPID
$returnUrl = 'http://www.xxx.com/alipay/return.php'; //付款成功后的同步回调地址
$notifyUrl = 'http://www.xxx.com/alipay/notify.php'; //付款成功后的异步回调地址
$outTradeNo = date('YmdHis') . rand(100, 999); //你自己的商品订单号
$payAmount = 0.01; //付款金额，单位:元
$orderName = '支付测试'; //订单标题
$signType = 'RSA2'; //签名算法类型，支持RSA2和RSA，推荐使用RSA2
//商户私钥，填写对应签名算法类型的私钥，如何生成密钥参考：https://docs.open.alipay.com/291/105971和https://docs.open.alipay.com/200/105310
$saPrivateKey = '';
$aliPay = new AlipayService($appid, $returnUrl, $notifyUrl, $saPrivateKey);
$payConfigs = $aliPay->doPay($payAmount, $outTradeNo, $orderName, $returnUrl, $notifyUrl);
class AlipayService {
	protected $appId;
	protected $returnUrl;
	protected $notifyUrl;
	protected $charset;
	//私钥值
	protected $rsaPrivateKey;
	public function __construct($appid, $returnUrl, $notifyUrl, $saPrivateKey) {
		$this->appId = $appid;
		$this->returnUrl = $returnUrl;
		$this->notifyUrl = $notifyUrl;
		$this->charset = 'utf8';
		$this->rsaPrivateKey = $saPrivateKey;
	}
	/**
	 * 发起订单
	 * @param float $totalFee 收款总费用 单位元
	 * @param string $outTradeNo 唯一的订单号
	 * @param string $orderName 订单名称
	 * @param string $notifyUrl 支付结果通知url 不要有问号
	 * @param string $timestamp 订单发起时间
	 * @return array
	 */
	public function doPay($totalFee, $outTradeNo, $orderName, $returnUrl, $notifyUrl) {
		//请求参数
		$requestConfigs = array(
			'out_trade_no' => $outTradeNo,
			'product_code' => 'QUICK_WAP_WAY',
			'total_amount' => $totalFee, //单位 元
			'subject' => $orderName, //订单标题
		);
		$commonConfigs = array(
			//公共参数
			'app_id' => $this->appId,
			'method' => 'alipay.trade.wap.pay', //接口名称
			'format' => 'JSON',
			'return_url' => $returnUrl,
			'charset' => $this->charset,
			'sign_type' => 'RSA2',
			'timestamp' => date('Y-m-d H:i:s'),
			'version' => '1.0',
			'notify_url' => $notifyUrl,
			'biz_content' => json_encode($requestConfigs),
		);
		$commonConfigs["sign"] = $this->generateSign($commonConfigs, $commonConfigs['sign_type']);
		return $commonConfigs;
	}
	public function generateSign($params, $signType = "RSA") {
		return $this->sign($this->getSignContent($params), $signType);
	}
	protected function sign($data, $signType = "RSA") {
		$priKey = $this->rsaPrivateKey;
		$res = "-----BEGIN RSA PRIVATE KEY-----\n" .
		wordwrap($priKey, 64, "\n", true) .
			"\n-----END RSA PRIVATE KEY-----";
		($res) or die('您使用的私钥格式错误，请检查RSA私钥配置');
		if ("RSA2" == $signType) {
			openssl_sign($data, $sign, $res, version_compare(PHP_VERSION, '5.4.0', '<') ? SHA256 : OPENSSL_ALGO_SHA256); //OPENSSL_ALGO_SHA256是php5.4.8以上版本才支持
		} else {
			openssl_sign($data, $sign, $res);
		}
		$sign = base64_encode($sign);
		return $sign;
	}
	/**
	 * 校验$value是否非空
	 *  if not set ,return true;
	 *    if is null , return true;
	 **/
	protected function checkEmpty($value) {
		if (!isset($value)) {
			return true;
		}

		if ($value === null) {
			return true;
		}

		if (trim($value) === "") {
			return true;
		}

		return false;
	}
	public function getSignContent($params) {
		ksort($params);
		$stringToBeSigned = "";
		$i = 0;
		foreach ($params as $k => $v) {
			if (false === $this->checkEmpty($v) && "@" != substr($v, 0, 1)) {
				// 转换成目标字符集
				$v = $this->characet($v, $this->charset);
				if ($i == 0) {
					$stringToBeSigned .= "$k" . "=" . "$v";
				} else {
					$stringToBeSigned .= "&" . "$k" . "=" . "$v";
				}
				$i++;
			}
		}
		unset($k, $v);
		return $stringToBeSigned;
	}
	/**
	 * 转换字符集编码
	 * @param $data
	 * @param $targetCharset
	 * @return string
	 */
	function characet($data, $targetCharset) {
		if (!empty($data)) {
			$fileType = $this->charset;
			if (strcasecmp($fileType, $targetCharset) != 0) {
				$data = mb_convert_encoding($data, $targetCharset, $fileType);
			}
		}
		return $data;
	}
}
function isWeixin() {
	if (strpos($_SERVER['HTTP_USER_AGENT'], 'MicroMessenger') !== false) {
		return true;
	}
	return false;
}
$queryStr = http_build_query($payConfigs);
if (isWeixin()):
?>
<script type="text/javascript" src="ap.js"></script>
<script>
    var gotoUrl = 'https://openapi.alipay.com/gateway.do?<?=$queryStr?>';
    _AP.pay(gotoUrl);
</script>
<?php
else:
	header("Location:https://openapi.alipay.com/gateway.do?{$queryStr}");
endif;
?>
